Question

Which of the following will not function as a buffer solution?

$\left(i\right)$ $NaCl$ and $NaOH$
$\left(ii\right)$ $NaOH$ and ${NH}_{4}OH$
$\left(iii\right)$ ${CH}_{3}COO{NH}_4$ and $HCl$
$\left(iv\right)$ Borax and boric acid

• A. $\left(i\right),\left(ii\right),\left(iii\right)$
• B. $\left(ii\right),\left(iii\right),\left(iv\right)$
• C. $\left(i\right),\left(iii\right),\left(iv\right)$
• D. $\left(i\right),\left(ii\right),\left(iii\right),\left(iv\right)$

Answer 1

The correct option is A $\left(i\right),\left(ii\right),\left(iii\right)$

A buffer solution is a salt of either weak acid and its salt with a strong base ($AcOH+NaOAc$) or a weak base and its salt with a strong acid ($N{H}_3+N{H}_{4}Cl$).

(i) $NaCl$ and $NaOH$ consists of salt of strong acid and strong base.

(ii) $NaOH$ and $N{H}_{4}OH$ consists of a weak base and strong base.

(iii) $C{H}_{3}COON{H}_4$ and $HCl$ consists of strong acid and a salt.

(iv) Borax and boric acid is an acid buffer solution. It consists of a weak acid (boric acid) and it's salt (borax) with a strong base.

Hence, option A is correct.